Jeff--thanks for reminding me that we didn't make mention of that sooner! We've been so busy pulling the next CTP together and getting ready for PDC that making that note hadn't percolated up yet.
I just added a post to our team blog about this: http://blogs.msdn.com/modelcitizen/archive/2009/11/02/next-oslo-ctp-to-be-released-in-conjunction-with-pdc.aspx
The short of it is that yes, there were incompatibilities with Beta 2 which the next CTP corrects, and that CTP will be available when PDC begins on Nov 17th.
Thanks again, and my apologies that we hadn't put out a notice sooner.
.Kraig